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handling.meta field · Aero and body

fMass

Mass

fMass is the mass of the vehicle in kilograms. It governs collisions, momentum and how much other vehicles push it, but not straight-line performance, because the drive force is defined per kilogram.

Unit
kg
stored as is, inverse mass in the physics instance
Vanilla median
1,628
Rhino tank 60,000, RC Bandito 85
Straight line
no effect
drive force and drag are per kg
Applies
respawn
physics instance is built at spawn

The myth first

Almost every handling tutorial says a lighter car accelerates faster. In GTA V it does not. The engine field fInitialDriveForce is a force per kilogram, and air drag is applied as an acceleration too. Halve the mass and the car launches, shifts and tops out exactly as before.

You can check this without trusting us. Put a Sultan at 800 kg and one at 3,200 kg on a straight and both cross the line together. The lab below shows the same thing: the speed numbers stay frozen while the mass slider moves.

Try it on a real car

The two boxes scale with mass. That ratio is the only thing you are changing.

Sport
MassfMass · needs a respawn
3008000
stock 1400

Vehicle mass. Decides who wins a collision and how mods weigh in. Acceleration is per kilogram, so mass alone does not slow the car.

Open this in the editor
Top speed
173km/h
does not move
0-100
5.88s
does not move
Push in a crash
0.86×
vs a 1,627 kg median car

Who moves whom

Sultan · 1,400 kg
median car · 1,627 kg

Acceleration is computed per kilogram, so the straight-line numbers stay put. Momentum in a collision scales with mass, and so does the push you get from a shunt.

What mass really controls

Momentum. When two vehicles meet, the heavier one keeps its direction. A 5,000 kg truck shoves a 1,300 kg hatchback aside, and the hatchback barely slows the truck. Ramming, pit manoeuvres and pushing a stuck car all read this field.

Mass also decides how tuning mods weigh in. Vehicles with the HF_REDUCED_MOD_MASS bit in strHandlingFlags gain less mass from parts. And the physics instance uses it for the inertia that vecInertiaMultiplier then scales.

In the lap-time model, fitted on 482 measured laps, mass has a coefficient so small that doubling it costs about 0.16 s. That is a statistical echo of heavy cars having other slow traits, not a physical effect.

Values in the game

Cars pile up between 1,000 and 2,000 kg. The long tail on the right is trucks, buses and military vehicles.

Computed from the 608 vanilla cars that have a public measurement, one entry per handling name. Motorcycles (49) are kept out of the chart; they run 100 to 1140.

608 vanilla cars
median 1,628 kg · 80 % sit between 1,040 and 5,150
5007,25014,000

Bars cover the 1st to 99th percentile. Extremes: 85 (RC Bandito) to 60,000 (Rhino Tank).

By vehicle class
  1. Compacts · 14650 990 1,400
  2. Sports Classics · 49800 1,400 2,420
  3. Super · 60880 1,400 3,000
  4. Sports · 117450 1,500 3,200
  5. Muscle · 81700 1,590 5,000
  6. Sedans · 44965 1,625 3,750
  7. Coupes · 19950 1,800 3,000
  8. Emergency · 31250 1,930 12,500
  9. Off-Road · 5785 2,000 8,600
  10. SUVs · 451,500 2,400 5,500
  11. Vans · 222,000 2,500 7,500
  12. Utility · 21400 4,950 10,400
  13. Industrial · 113,800 6,000 35,000
  14. Service · 101,400 8,250 14,000
  15. Commercial · 155,500 9,000 14,000
  16. Military · 12301 9,500 60,000

Five cars from the bottom to the top

  1. Lowest
    85kg
    RC Bandito
    Off-Road
  2. 25th percentile
    1,350kg
    Gauntlet Classic
    Muscle
  3. Median
    1,630kg
    Impaler LX Cruiser
    Emergency
  4. 75th percentile
    2,400kg
    Chino Custom
    Muscle
  5. Highest
    60,000kg
    Rhino Tank
    Military

What to change instead

You wantChange
Quicker launchfInitialDriveForce, and check the grip cap
Higher top speedfInitialDragCoeff down, or fInitialDriveMaxFlatVel up
Car feels planted, less floatyvecInertiaMultiplier z above 2, vecCentreOfMassOffset z lower
Wins collisionsthis field

Keep the value realistic for the model. Tiny masses make the car bounce off kerbs like a toy, and a 60,000 kg sports car becomes a wrecking ball that nobody wants on a roleplay server.

Related fields

Numbers on this page come from the vanilla handling files of GTA V (one entry per handling name, 55 fields catalogued) and from a speed model checked against 617 measured top speeds. Published 2026-09-08. Not affiliated with Rockstar Games or Cfx.re.